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Concussion

The most common type of traumatic brain injury is called a Concussion. The word comes from the Latin concutere, which means "to shake violently."

According to the CDC, in the US, between 2001 and 2009, an estimated 173,285 people under age 19 were treated in hospital emergency rooms for concussions related to sports and recreation activities. Other causes include car and bicycle accidents, work-related injuries, falls, and fighting.

As seen in countless Saturday morning cartoons, a concussion is most often caused by a sudden direct blow or bump to the head.

The brain is made of soft tissue. It's cushioned by spinal fluid and encased in the protective shell of the skull. When you sustain a concussion, the impact can jolt your brain. Sometimes, it literally causes it to move around in your head. Traumatic brain injuries can cause bruising, damage to the blood vessels, and injury to the nerves.

The result? Your brain doesn't function normally. If you've suffered a concussion, vision may be disturbed, you may lose equilibrium, or you may fall unconscious. In short, the brain is confused. That's why Bugs Bunny often saw stars.

Concussions can be tricky to diagnose. Though you may have a visible cut or bruise on your head, you can't actually see a concussion. Signs may not appear for days or weeks after the injury. Some symptoms last for just seconds; others may linger.

Concussions are fairly common. Some estimates say a mild brain trauma is sustained every 21 seconds in the U.S. But it's important to recognize the signs of a concussion so you can take the proper steps to treat the injury.

There are some common physical, mental, and emotional symptoms a person may display following a concussion. Any of these could be a sign of traumatic brain injury: